Administrative Core. This administrative Core will have both scientific and organizational responsibilities. The scientific aspects will be carried out by Dr. Kwiatkowski. He will advise investigators on strategic and technical issues, promote collaboration and contact among projects, monitor the functions and effectiveness of the core facilities, and assess the scientific quality and progress of the work. This will require active interactions with all groups on a regular basis. Any scientific problems or organizational issues that arise will be discussed first with the co-Pi, Dr. Cantley. There will also be an Internal Advisory Board composed of senior scientists in the Boston area, who will meet on an ad hoc basis to assist with any scientific or organizational issues. There will also be an External Advisory Board composed of senior scientists from outside Boston. There will be annual all-day meetings at which all Project and Core Investigators will present research progress and plans to members of the Internal and External Advisory Board. Organizational aspects of the PPG will be handled by Dr. Kwiatkowski and the Administrative Coordinator, Ms. Karen Vengerow. She will organize all interactions among the projects and the cores, including arranging for the annual meeting, and deal with all other administrative aspects including preparation of all progress reports and applications related to this PPG.